He has denied murdering Khanokporn Satjawat, 42, from Thailand, at the Clyde Auditorium on 12 November 2012.

Carter has lodged a special defence, admitting culpable homicide due to diminished responsibility.

Mrs Satjawat died while attending a conference for HIV drug therapy at the Clyde Auditorium, which is part of the SECC complex.

She sustained massive head and facial injuries after being battered with a fire extinguisher in a female toilet.

The court was heard how Mrs Satjawat's blood was found on Carter's trousers and on the sleeve of his work blazer and cuffs of his shirt.

His DNA was also found on the sleeve of the jumper Mrs Satjawat was wearing.

Carter, from Motherwell, North Lanarkshire, was working as a security guard at the venue at the time of the incident.

He has claimed he has no memory of the killing.

He said he remembered arguing with his victim and the next thing he recalled was eating his sandwiches for lunch minutes later.

'No memory'

Giving evidence for a second day, father-of-three Carter was asked by advocate depute John Scullion, prosecuting: "Did you tell a psychiatrist that you have always known that you were responsible for the killing of Khanokporn Satjawat?"

Image caption
Khanokporn Satjawat was attending a pharmaceutical conference when she died

He replied: "I was looking back on things. At the time of the incident I wasn't fully aware, it was only after having time to reflect."

Carter was asked why he had lied to the police and told them he had seen an Asian man walking about with a fire extinguisher and had taken it from him.

He replied: "At the time I thought I was helping the police."

Bloodstained clothing

When asked if he had in fact seen an Asian man Carter said: "In my head, yes."

Mr Scullion said: "Was it because you knew that two delegates had seen you with a fire extinguisher," and Carter replied: "I don't know."

He then added: "At the time I didn't know that."

Carter also told the jury he had no memory of washing blood from the fire extinguisher and then hiding it in a room in the complex.

Mr Scullion said: "You took the fire extinguisher down from the second floor to room 136 and the purpose for that was to clean it of blood," and Carter replied: "I don't remember."